While its authenticity can't be verified -- and BlackBerry won't comment on it -- the image shows a qwerty keyboard-ready smartphone that is more angular than the current and widely-used BlackBerry Curve devices.

The forum contributor calls the device the first in the BlackBerry R-series, which has been expected for some time as the BB 10 update to Curve.

Separately, BlackBerry Empire has posted a sketch of what could be of a BlackBerry R-series device. The sketch shows slots for an external SD card and MicroSIM.

Various reports have described the R-Series device as having an 100 mAh battery (the same as the BlackBerry Z10) and 8 GB of internal storage, half the capacity of the Z10 or qwerty Q10.

The specs may indicate that the R-Series will be a lower-priced BlackBerry device. Reports have speculated that the R-Series device will be priced at a bit more than $300 without a contract, or about half of what high-end smartphones sell sans contract today, reports have said.

The Blackberry R-series device will be released in the third or fourth quarter of 2013, according to several reports. The timing jives with comments about upcoming products made by BlackBerry CEO Thorsten Heins to analysts during the company's fourth quarter earnings call.

While the R-series image and sketch on the BlackBerry Empire site can't be verified, images of several BlackBerry devices posted before the products were announced were accurate. Those included images of the Z10 and Q10 that ran on the CrackBerry site months before they were announced in late January.

Last week, a purported BlackBerry roadmap appeared in a tweeted image from @BB10Leaks that shows a larger tablet and two phone-tablet, or phablet, devices coming in the next 12 months.